Manufacture of cement.



- UNITED STATES PATENT OFFICE.

JACOB STEIGER, OF LONDON, ENGLAND.

MANUFACTURE OF CEMENT.

SEOIFIGATION forming part of Letters Patent No. 694,802, dated March 4, 1902.

Application filed July 8, 1901. erial No. 679537. (No specimens.)

To all whom, it may concern:

Be it known that I, JACOB STEIGER, manufacturer, a subject of the King of Great Britain, residing at and whose postal address is 24 Finsbury Square, London, England, have invented certain new and useful Improvements in the Manufacture of Oement,of which the following is a specification.

My invention relates to the production of a dry magnesia cement containing silicasuch, for instance, as that for which Letters Patent were granted to me, No. 627,884; and the object of my present invention is to effect an improvement in. the process of manufacturing a cement of thisdescription, whereby the same is simplified and the cost of the production of such cement is cheapened.

According to my invention instead of mixing a solution of silicate of soda or potash (water-glass) with the solution of magnesium chlorid I now use the water-glass and other silicates in a solid form and preferably in their raw state. As examples of solid silicates in the raw state that may be used may be mentioned coal, iron, and other slags, trass, pozzuolana earth, lava, granite, basalt, and-the like.

In my said former patent the mixture of chlorid of magnesium and silicate of potash or soda in solution is allowed sufficient time to split up the ingredients andchange over,

- 'no heat being applied until after these chemical changes have taken place. which may be represented thus:

mass undergoes chemical changes of a totally-- difierent character to those which follow the cold treatment before referred to. The application of comparatively great heat decomposes the chlorid of magnesium, forming oxid of magnesium and hydrochloric acid-e; g.,

yield its silicate in the form of a hydrated silicic acide. g.,

1 'QHGH-Na SiO, (solid water-glass):

- 2NaCl+H,SiO,)

2 GHCl-i- Fe,O,Si() (iron slag):

Fe Ol +H Si0,) 3- 6H6L+Al O SiO (slag or granite):

Al Cl +H SiO,) .The heating is continued, until the mass is evaporated nearly to dryness, when after coolingand sti flening it is crushed and ground to a fine powder. The hydratic silicic acid, which possesses great hardening or cementing properties, remains inert whether or not mixed with the powdered calcined magnesite, (magnesia) Only on adding water to the cement material (containing calcined mag nesite) for immediate use, the hydratic silicic acid commences to exert its cementing powers upon the admixed calcined magnesite, producing a remarkably hard substauce,whether used as cement or when'mixed with filling materials to form artificial stone, artificial fuel-blocks,and other articles in which cement gives coherence to the materials.

The proportions, by weight, ofthe ingredients best suitable are as followsz-Chloride of magnesium, MgOl )=8O-9O parts silicious matter (say slag or granite) 20-30 parts calcined magnesite 150-200 parts.

I claim 1. The process for the manufacture of a silicated magnesia cement in dry form, which consists in mixing a concentrated hot solution of chlorid of magnesium with a powdered silicious material, heating the same to and above 130 centigrade, reducing the mass to a dry powder by continued heating and add ing calcined magnesite, substantially as set forth.

2. The process for the manufacture of a silicated magnesia cement in dry form, consisting of mixing a concentrated solution of chlorid of magnesium with a powdered silicious material in suitable proportions, heating such mixture to form a hydrated silicic acid of the silicious raw material, evaporating, drying and powdering the mixture, and adding thereto a suitable proportion of pow dered calcined magnesite, substantially as set IO forth.

In testimony whereof I have hereunto set my hand in presence of two subscribing wit- IIGSSGS.

JACOB STEIGER. Witnesses:

GEORGE O. DOWNING, WILMER M. HARRIS. 

